Is zedna a planet or an asteroid?

Answer 1

Neither. Its a kuiper belt object. It is beleived to the tenth planet, but it is actually to small to be a planet. It is only 1000 miles big! It however, does hold the record for the most distant object from the sun. At its closest point, it is 8 billion miles away. At the farthest, it is 80 billion miles away, and marks one of the boundery points for the edge of the solar system.

and its actually spelled "sedna"

Answer 2

Currently there is no official definition of a planet. In my opinion, Pluto, Sedna, and anything else they find out there beyond Neptune's orbit should be labeled as Kuiper Belt objects, and not planets, but that's just my opinion. The International Astronomical Union has the final say on definitions and names of all objects in space - they are actually going to define what a planet is (and whether or not Pluto is a planet) this September. No matter what you classify them as, they are still interesting!

Answer 3

astronomers are trying to define the word planet, but it isn't easy. many astronomers favor the reclassification of the bodies in the solar system into three groups, the rocky terrestrials, the gas giants and the ice dwarfs. some even call uranus and neptune ice giants. there are hundreds of known ice dwarfs including pluto, quaoar, sedna, 2003 EL61, and 2003 UB313 (the official name of xena). this is also called the kuiper belt, and pluto was the first kuiper belt object discovered, but 2003 UB313 is about five percent bigger than pluto.

look here:
http://en.wikipedia.org/wiki/Kuiper_belt

i personally favor this reclassification.

Answer 4

Zedna is considered to be the tenth planet.